CVE-2026-93689

WinFsp through 2.2.26215 contains a null pointer dereference vulnerability in the kernel driver's Fast I/O device control handler that fails to validate the volume context before use. An unprivileged local user can trigger a denial of service by opening the WinFsp control device and issuing FSP_IOCTL_TRANSACT requests, causing a system crash.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/winfsp/winfsp
https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L105-L114
https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L146-L152
https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L68-L73
https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/volume.c#L1059-L1060
https://github.com/winfsp/winfsp/commit/b8103265ec63fa87ac264c62bb796dbc38376652
https://github.com/winfsp/winfsp/releases/tag/v2.2B4
https://www.vulncheck.com/advisories/winfsp-through-2.2.26215-null-pointer-dereference-via-fast-i-o

Configurations

No configuration.

History

18 Sep 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 16:17

Updated : 2026-09-22 20:25

NVD link : CVE-2026-93689

Mitre link : CVE-2026-93689

CVE.ORG link : CVE-2026-93689

JSON object : View

Products Affected

No product.

CWE

CWE-476

NULL Pointer Dereference

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